NBER Working Papers and Publications

This paper investigates whether compulsory licensing – which allows governments to license patents without the consent of patent-owners – discourages invention. Our analysis exploits new historical data on German patents to examine the effects of compulsory licensing under the US Trading-with-the-Enemy Act on invention in Germany. We find that compulsory licensing was associated with a 28 percent increase in invention. Historical evidence indicates that, as a result of war-related demands, fields with licensing were negatively selected, so OLS estimates may underestimate the positive effects of compulsory licensing on future inventions.